Imparting meat flavor with 3-furylthioesters

ABSTRACT

WHEREIN R1 is C1-C7 straight chain or branched chain alkyl or alkenyl; or R1 is either furyl, thienyl, toluyl, phenyl ethenyl or phenyl; and wherein each of R2, R3 and R4 is the same or different hydrogen or lower alkyl together with compositions containing the 3-thia furans for use in altering such organoleptic properties.   Methods for altering the organoleptic properties of foodstuffs comprising incorporating with such foodstuffs a small but effective amount of at least one 3 thia furan having the formula:

United States Patent [191 Evers et al.

[ Mar. 25, 1975 IMPARTING MEAT FLAVOR WITH 3-FURYLTHIOESTERS [75]Inventors: William J. Evers, Atlantic Highlands; Howard H. Heinsohn,.llr., Hazlet; Bernard J. Mayers, Clifford Beach; Elizabeth A. Karol],Old Bridge, all of NJ.

[73] Assignee: International Flavors & Fragrances Inc., New York, NY.

22 Filed: Aug. 7, 1973 21 Appl. No.: 386,451

Primary Examiner-Joseph M. Golian Attorney. Agent, or Firm-Arthur L.Liberman, Esq.', Harold Haidt, Esq.

[57] ABSTRACT Methods for altering the organoleptic properties offoodstuffs comprising incorporating with such foodstuffs a small buteffective amount of at least one 3 thia furan having the formula:

wherein R is C,C straight chain or branched chain alkyl or alkenyl; or Ris either fury], thienyl, toluyl, phenyl ethenyl or phenyl; and whereineach of R R and R is the same or different hydrogen or lower alkyltogether with compositions containing the 3thia furans for use inaltering such organoleptic properties.

20 Claims, N0 Drawings IMPARTING MEAT FLAVOR WITH 3-FURYLTH1OESIERSBACKGROUND OF THE lNVENTlON The present invention provides methods foraltering the organoleptic properties of foodstuffs by adding to suchfoodstuffs quantities of one or more 3-thia furans and it furtherrelates to compositions adapted to alter the organoleptic properties offoodstuffs.

Artificial flavoring agents for foodstuffs have received increasingattention in recent years. In many areas, such food flavoring agents arepreferred over natural flavoring agents at least in part because of theuniform flavor that may be so obtained. For example, natural foodflavoring agents such as extracts, essences, concentrates and the likeare often subject to wide variation due to changes in the quality, typeand treatment of the raw materials. Such variation can be reflected inthe end product and results in unreliable flavor characteristics anduncertainity as to consumer acceptance and cost. Additionally, thepresence of the natural product in the ultimate food may be undesirablebecause of increased tendency to spoil. This is particularly troublesomein convenience and snack food usage where such products as dips, soups,chips, prepared dinners, canned foods, sauces, gravies and the like areapt to be stored by the consumer for some time prior to use.

The fundamental problem in preparing artificial flavoring agents is thatof achieving as nearly as possible a true flavor reproduction. Thisgenerally proves to be a different task since the magnetism for flavordevelopment in many foods is not understood. This is noteable inproducts having meaty and roasted flavor characteristics. It is alsonoteable in products having vegetablelike and hydrolyzed vegetableprotein-like and aniselike flavor characteristics.

Reproduction of roasted and meat flavors and aromas and vegetable-likeand hydrolyzed vegetable protein-like and aniselike flavors and aromashas been the subject of the long and continuing search by those engagedin the production of foodstuffs. The severe shortage of foods,especially protein foods, in many parts of the world has given rise tothe need for utilizing nonmeat sources of proteins and making suchproteins as palatable and as meat-like as possible. Hence, materialswhich will closely simulate or exactly reproduce the flavor and aroma ofroasted meat products and liver products and vegetable products arerequired.

Moreover, there are a great many meat containing or meat based foodspresently distributed in a preserved form. Examples being, condensedsoups, dry-soup mixes, dry meat, freeze-dried or lyophilized meats,packages gravies and the like. While these products contain meat or meatextracts, the fragrance, taste and other organoleptic factors are veryoften impaired by the processing operation and it is desirable tosupplement or enhance the flavors of these preserved foods withversatile materials which have either roasted meat or gravy-like orvegetable-like or meat-like or ham-like nuances.

US. Pat. No. 3,666,495 provided materials having such desirable meat,roast meat and roasted fragrance and flavor notes. Such materials areorganic oxygen containing heterocyclics wherein the second carbon atomfrom the oxygen atom contains a sulfur substituent and included 3-thiafuran compounds having the structure:

g. (& 'r Qmf a See pages 6 and 7 of the said South African patent.

Volume 24 Food Technology page 535 (May, 1970) [the Gras IV listNo.3l62] discloses the use as a flavor adjuvant furfural S thioacetatehaving the structure:

Nothing in the prior art, however, sets forth implicitly or explicitlythe 3-furyl thioesters of our invention and their unique andadvantageous and unobvious flavor properties.

THE INVENTION The present invention provides methods for altering theorganoleptic properties of foodstuffs which comprise adding to suchmaterials at least one 3-thia furan. Briefly, the methods compriseadding an amount of at least one thia furan having the formula:

wherein R is C,C straight chain or branched chain alkyl or alkenyl or Ris either fury], thienyl. toluyl. phenyl ethenyl or phenyl; wherein eachof R R and R is the same or different hydrogen or lower alkyl to a foodstuff to change the organoleptic properties of said foodstuff. Theinvention also contemplates compositions containing such 3-thia furancompounds.

Preferred 3thia furans useful in our invention are as follows:

3-thio acetyl furan 2,5-dimethyl-3-thio acetyl furan 2-methyl-3-thioacetyl furan 2,5-dimethyl-4-ethyl-3-thio acetyl furan 2-methyl-3-thioisobutyryl furan 2.5-dimethyl-3-thio isobutyryl furan2,5-dimethyl-3-thio isovaleryl furan 2-dimethyl-3-thio isovaleryl furan2-methyl3(2 thi furoyl) furan 2.5-dimethyl-3(2-thio furoyl) furan2-methyl-3thio octanoyl furan ,5-dimethyl-3-thio octanoyl furan,5-dimethyl-3-thio benzoyl fur-an .5-dimethyl-3-thio propionyl furan-methyl-3thio pivaloyl furan ,S-dimethyl-B-thio pivaloyl furan,5-dimethyl-3-thio hexanoyl furan -propyl-3-thio acetyl furan,5-dimethyl-3-thio(Z-methyl-Z-pentenoyl) furan .5-dimethyl-3thio toluoylfuran .5-dimethyl'3-thio cinnamoyl furan 2.5-dimethyl-3-thio(Z-methyl-Z-pentenoyl) furan The novel compounds of our invention may beproduced according to processes which comprise the steps of:

i. providing a 2ene-l,4 dione having the structure:

"/5 0 R R, "m z ii. intimately admixing said 2-ene-l,4 dione with a thioacid having the formula R S H thereby providing a substituted orunsubstituted Z-thia substituted l 4 dione having the structure:

iii. cyclizing said 2-thia substituted 1,4 dione to form a substitutedor unsubstituted 3-th ia furan having the formula:

v. reacting the thus formed 3-mercapto furan with an acylating oraroylating agent thus forming a new acyl or aroyl 3-thia furan havingthe structure:

wherein R is straight chain or branched chain allql or alkenyl havingfrom l up to 7 carbon atoms or R is either of fury], thienyl, toluyl,phenyl ethenyl. or phenyl; wherein each of R R and R is the same ordifferent hydrogen or lower alkyl; wherein R is acyl or aroyl; andwherein R is acyl or aroyl different from R R or- /and R may each behydrogen in the event that in step (ii) the 2-ene-l,4 dione is admixedwith the thio acid having the formula R Sl-l in the presence of anorganic base such as piperidine, pyridine, triethyl amine. quinoline ora-picoline or a mixture thereof.

The 2-ene-l,4 dione may be prepared by reacting 2,5-dialkoxy-2,5dialkyl-2,5dihydrofuran with a weak acid hydrolysis agent such as 1%aqueous acetic acid under reflux conditions. The resulting material willbe in the case of starting with 2,5-dimethoxy-2,5-dimethyl-2,5-dihydrofuran, cisJ-hexen-Zj-dione The resulting 2-ene-l,4dione is then reacted with a thio acid having the formula R SH wherein Ris either acyl or aroyl.

Examples of such thio acids are:

Thioacetic acid Thiopropionic acid Thiobutyric acid Thioisobutyric acidThio-n-pentenoic acid Thiocinnamic acid Thiobenzoic acid- Z-MethylThiobenzoic acid B-Methyl Thiobenzoic acid 4-Methyl Thiobenzoic acid2,4-Dimethyl Thiobenzoic acid 3,5-Dimethyl Thiobenzoic acid Whether anorganic base is used or not in the reaction with the 2-enel ,4 dionewith the thio acid having the formula R SH, the 2-ene-1,4 dione can beexemplifled as follows:

Compound R. R R Name 3-Hexen-2,5-dione Methyl Methyl Hydrogen3-Methyl-3-hexen25 Methyl Methyl Methyl dione 3-Methyl-3-hepten-2,5Methyl Ethyl Methyl dione 3-Ethyl-3-hepten-2,5 Methyl Ethyl Ethyl dione4-Ethyl-4-octen-3.6 Ethyl Ethyl Ethyl dione 3Propyl'3-hcpten-2.5 MethylEthyl Propyl dione 4-Methyl3-heptcn2.5 Ethyl Methyl Methyl dione4Methyl-4-octen-3,b Ethyl Ethyl Methyl dione 4-Methyl-4-nonen-3b EthylPropyl Methyl dione 4Propyl-3-hcpten-3,6 Ethyl Methyl Propyl dioneS-Methyl-S-decenw-l] Propyl Propyl Methyl dione 5-Methyl4nunen-3,6Propyl Ethyl Methyl dione 4-Methyl-3-nonen-2,5 Butyl Methyl Methyl dione4-Ethyl-3-nonen-l5 Butyl Mcthyl Ethyl dione 3 Methyl-3-nonen-2,5 MethylButyl Methyl dione 3-Propyl-3-nonen'l5 Methyl Butyl Propyl dione 3-Butyl3-hexen-2,5 Methyl Methyl Butyl dione 4-Octen-3,6-dione Ethyl EthylHydrogen As stated above, R and R can each be hydrogen for the purposesof these processes of our invention in the event that in the reaction ofthe Z-ene-l ,4 dione with the thio acid of the formula R SH, an organicbase is used. Hence, in addition to the foregoing compounds, thefollowing compounds can be utilized in the reaction Examples of usefulorganic bases are piperidine, py ridine, quinoline, triethyl amine anda-picoline. In place such as benzoyl peroxide or azobisisobutyl nitrile.The

of such organic bases, radical initiators may be used reaction may be iscarried out in a solvent such as water or an ether such as diethyl etheror a hydrocarbon such as benzene or hexane or cyclohexane. The reactionI may also be carried out without the use of a solvent. The reaction maybe is carried out under reflux conditions although temperatures varyingfrom 0 up to 60C are suitable and will give rise to commerciallysuitable yields. Examples of reaction products, 2-thia substitut-' 6ed-l,4-diones which are formed from the reaction of the Z-ene-l ,4diones with the thio acids having the formula R SH are as follows:

The foregoing 2-thia substituted l,4 diones are then cyclized to formsubstituted or unsubstituted 3- thiafurans according to the followingreaction:

wherein R and R are the same or different and are each hydrogen or loweralkyl; wherein R is either acyl or aroyl and R is hydrogen or loweralkyl. The resulting 3-thiafurans (novel compounds of our invention) maybe used as such for their organoleptic properties or they may behydrolyzed and then re acylated or rearoylated to form other acyl thiaor aroyl thia substituted furans (other novel compounds of ourinvention) which have still other organoleptic properties useful forflavoring foodstuffs.

The cyclization reaction carried out in cyclizing the 2-thiasubstituted-l ,4-dione is carried out in the presence of a cyclizationagent, preferably, isopropenyl acetate. The cyclization is also carriedout in the presence of such a catalyst as concentrated sulfuric acid.zinc chloride, boron trifluoride, aluminum trichloride, and paratoluenesulfonic acid, each of these being acid catalysts. Preferably, the ratioof isopropenyl acetate to 2-thia substituted 1,4 dione is 4 to 5:1. Theratio of acid catalyst to isopropenyl acetate is from 0.00l up to 0.05(mole ratio). The cyclization reaction may be run at temperatures ofbetween 25C up to reflux at atmospheric pressure (96C). Still greaterreflux temperatures may be used if the pressure is greater thanatmospheric. Furthermore, in place of isopropenyl acetate as acyclization reagent, acetic anhydride or propionic anhydride may beused. Ratios of acetic anhydride or propionic anhydride to 2-thiasubstituted 1,4 dione are preferably 4 to 5:1 (mole ratio).

In the event that the resulting 3-thia furan is desired to be used as afood flavor additive, the reaction product is purified by appropriateextraction and distillation techniques. Thus, the following 3-thiafurans of our invention produced in this manner have useful organolepticproperties giving rise to their use as foodstuff flavors as set forth inan illustrative manner in the follow ing table:

Z-Thi a Substituted l.4-d|one Renctanl 3-Thio Furan Reaction ProductFlavor lro erties of 3-Thia uran Reaction Product 3-Thio benZoyI-LShexane dione 2,5dimethyI-3- thio benzoyl furan at 2 ppm (threshholdvalue 0.05 ppm) Sweet floral orseradish f ragrance Cooked chicken-likearoma with roasted meat nuance; fatty floral-like eggy flavor at 2 ppm(threshold 0.1

ide. The mole ratio of base to 3-thia furan is preferably 1:] but may beas high as 3:1 or as low as 0.01:1. ln atl- An optional additional stepis hydrolysis'of the 3-thia furan to form 3-mercapto furan having thestructure:

The hydrolysis reaction is carried out in the presence 40 of strongaqueous base, for example, sodium hydroxide, potassium hydroxide, sodiumcarbonate, lithium carbonate. potassium carbonate and lithiu m hydroxName of Compound dition to solely aqueous solutions of base. mixtures ofalcohol (e.g., methanol and ethanol) and water may be used as solventsin the hydrolysis reaction. The hydrolysis temperature may vary fromroom temperature to reflux. In the event that the basic solution is asolution which is alcoholic (substantially purely alcoholic) the alkalimetal thiafuran may be formed.

Reacylation of the 3-furan thiol to yield still other acyl thiafurans oraroyl thiafurans is carried out by reaction of the appropriate acyl oraroyl halide with the 3-furan thiol in the presence of an appropriatesolvent such as diethyl ether, tetrahydro furan, or cyclohexane and inthe presence of preferably a strong organic base such as pyridine ora-picoline. Thus, the following table sets forth the several compoundswhich can be conveniently formed having a large number of organolepticproperties giving rise to a wide field of flavor uses:

Organoleptic Property 2-Methyl-3-thio-isobutyl furan 2,5-Dimethl-3-thioisobutyl uran 2,5-Dimethyl-3-thioisovaleryl furan2-Methyl-3-thio-isovaleryl furan 2-MethyI-3( Z-thiofuroyl) furan2.5-Dimethyl-3( 2-thio furoyl )furan Meaty, ham, green vegetable aroma;ham-like meaty vegetable nutty flavor at 0.1 ppm concentration Creamycocoa-like sweet aroma. Cocoa powder creamy green flavor at 0.1 ppmconcentration Green meaty vegetable-like aroma Green meatyvegetable-like HVP-like flavor at 0.] ppm concentration HVP-like, meatyaroma; HVP- like, liver-like meaty flavor at 0.02 ppm concentrationHVP-like, meaty aroma. HVP- like meaty flavor at ().l ppm Name ofCompound Organoleptic Property 2-Methyl-3-thio-octanoylfuran2,5-Dimethyl-3-thiooctanoyl furan 2,5Dimethy|-3-thio benzoyl furan2-Methyl-3-thiopivaloyl furan 2,5-Dimethy|-3-thiopivaloyl furan2,5-Dimethyl-3-thio'hexanoyl furan 2,5-Dimethyl-3-thiocinnamoyl furan2,5-Dimethyl-3-thio(mtoluoyl) furan 2,5-Dimethyl-3-thi0(2- Meaty, sour,floral aroma; meaty, sour, floral HVP-like flavor at 0.1 ppmconcentration Meaty brothy aroma; meaty, brothy, nutty aroma with HVPafter-taste at 0.] ppm concentration Cooked chicken-like roastedmeat-like aroma; florallike, fatty flavor at 2 ppm (0.] ppm threshold)Roasted meat, sweet aroma; roasted meat vegetable-like flavor at ().lppm concentratron Sweet-meaty chicken-like aroma; Sulfury meaty flavorat 0.5 ppm Meaty, green, creamy aroma; meaty, green, creamy, nuttyflavor at 0.5 ppm (0.1 ppm threshhold level) Meaty, brown sugar, greenwalnut aroma; meaty, rubbery, walnut sweet flavor at 2 ppmconcentration.

Roasted meat, liver, sulphury aroma; meaty, reen roasted meat liver,sulp ury fresh walnut kernal flavor at ppm.

Meaty, sweet, HVP, creamy methyl-Z-pentenoyl) aroma; sweet roasted meat,

furan rubbery flavor at 0.] ppm.

Thus, the 3-thiafuran derivatives and mixtures thereof according to thepresent invention can be used to alter, vary, fortify, modify, enhance,orotherwise improve the organoleptic properties, including flavor and-/or aroma, of a wide variety of materials which are ingested, consumed,or otherwise organoleptically sensed. The term alter in its variousforms will be understood herein to mean the supplying or imparting aflavor character or note to an otherwise bland, relatively tastelesssubstance, or augmenting an existing flavor characteristic where thenatural flavor is deficient in some regard, or supplementing theexisting flavor or aroma impression to modify the organolepticcharacter. The materials which are so altered are generally ref r d to?EEEWPWBPR.EU FFlEE...

Such 3-thiafuran derivatives are accordingly useful in flavoringcompositions. Flavoring compositions are herein taken to mean thosewhich contribute a part of the overall flavor impression bysupplementing or fortifying a natural or artificial flavor in amaterial, as well as those which supply substantially all the flavorand/or aroma character to a consumable article.

The term foodstuff as used herein includes both solid and liquidingestible materials for man or animals, which materials usually do, butneed not, have nutritional value. Thus, foodstuffs includes meats,gravies, soups, convenience foods, malt and other alcoholic ornon-alcoholic beverages, milk and dairy products, nut butters such aspeanut butter and other spreads, sea foods including fish, crustaceans,mollusks and the like, candies, breakfast foods, baked goods,vegetables, cereals, soft drinks. snack foods, dog and eat foods, otherveterinary products, and the like.

When the 3-thiafuran derivatives according to this invention are used ina food flavoring composition, they can be combined with conventionalflavoring materials or adjuvants. Such co-ingredients or flavoringadjuvants are well known in the art for such use and have beenextensively described in the literature. Apart from the requirement thatany such adjuvant material be ingestibly acceptable, and thus non-toxicor otherwise nondeleterious, conventional materials can be used andbroadly include other flavor materials, vehicles, stabilizers,thickeners, surface active agents, conditioners, and flavorintensifiers.

Examples of preferred coflavoring adjuvants arez' Methyl thiazolealcohol (4-methyl-5-Bhydroxyethyl thiazole);

2-Methyl butanethiol;

4-Mercapto-2-butanone;

3Mercapto4-pentanone;

l-Mercapto-Z-propanone;

Benzaldehyde;

Furfural;

Furfural alcohol;

Z-Mercapto propionic acid;

ZPentene;

Alkyl pyrazine;

Methyl pyrazine;

2-Ethyl-3-methyl pyrazine;

Tetramethyl pyrazine;

Polysulfides;

Dipropyl disulfide;

Methyl benzyl disulfide',

Alkyl thiophenes;

2-Butyl thiophene;

2,3-Dimethyl thiophene;

S-Methyl furfural;

Acetyl furan;

2,4-Decadienal;

Guiacol;

Phenyl acetaldehyde;

S-Decalactone;

d-Limonene;

Acetoin;

Amyl acetate;

Maltol;

Ethyl butyrate;

Levulinic acid;

Piperonal;

Ethyl acetate;

n-Octanal;

n-Pentanal;

Hexanal;

Diacetyl;

Monosodium glutamate;

Sulfur-containing amino acids;

Cysteine;

Hydrolyzed vegetable protein;

Hydrolyzed fish protein; and

Tetramethyl pyrazine The 3thiafuran derivatives, or the compositions incorporating them, as mentionedabove, can be combined with one or morevehicles or carriers for adding them to the particular product. Vehiclescan be edible or otherwise suitable materials such as ethyl alcohol,propylene glycol, water, and the like. Carriers include materials suchas gum arabic, carrageenan, other gums, and the like. The 3-thiafurancompounds according to this invention can be incorporated with thecarriers by conventional means such as spray-drying, drum-drying, andthe like. Such carriers can also include materials for coacervating the3-thiafuran derivatives (and other flavoring ingredients, as present) toprovide encapsulated products. When the carrier is an emulsion, theflavoring composition can also contain emulsifiers such as monoanddiglycerides of fatty acids and the like. With these carriers orvehicles, the desired physical form of the composition can be prepared.

The quantity of 3-thiafuran derivatives or mixtures thereof utilizedshould be sufficient to impart the desired flavor characteristic to theproduct, but on the other hand, the use of an excessive amount of thederivative is not only wasteful and uneconomical, but in some instancestoo large a quantity may unbalance the flavor or other organolepticproperties of the product consumed. The quantity used will varydepending upon the ultimate foodstuff; the amount and type of flavorinitially present in the foodstuff; the further process or treatmentsteps to which the foodstuff will be subjected; regional and otherpreference factors; the type of storage, if any, to which the productwill be subjected; and the preconsumption treatment, such as baking,frying, and so on, given to the product by the ultimate consumer.Accordingly, the terminology effective amount and sufficient amount isunderstood in the context ofthe present invention to be quantitativelyadequate to alter the flavor of the foodstuff.

It is accordingly preferred that the ultimate composi tions contain fromabout 0.02 parts per million (ppm) to about 250 ppm of 3-thiafuranderivative or derivatives. More particularly, in food compositions it isdesirable to use from about 0.05 ppm to 100 ppm for enhancing flavorsand in certain preferred embodiments of the invention, from about 0.2 to50 ppm of the derivatives are included to add positive flavors to thefinished product. All parts, proportions. percentages, and ratios hereinare by weight unless otherwise indicated.

The amount of 3-thiafuran material or materials of our invention to beutilized in flavoring compositions can be varied over a wide rangedepending upon the particular quality to be added to the foodstuff.Thus, amounts of one or more derivatives according to the presentinvention of from about 2 ppm up to 80 or 90 percent of the totalflavoring composition can be incorporated in such compositions. It isgenerally found to be desirable to include from about 10 ppm up to about0.1 percent of the 3-thiafuran derivatives in such compositions.

The following examples are given to illustrate embodiments of theinvention as it is preferably preferred to practice it. It will beunderstood that these examples are illustrative and the invention is notto be considered as restricted thereto except as indicated in theappended claims.

EXAMPLE 1 (Preparation of Cis-3-hexene-2,5-dione) In a 1000 ml roundbottom flask fitted with condenser and magnetic stirrer are placed 200 gof 2,5-

dimethoxy-2,5-dimethyl-2,5-dihydrofuran and 200 ml of a 1% aqueousacetic acid solution. The resulting solution is heated to reflux,refluxed for 2 minutes, cooled with an ice bath to 25C and 625 ml ofa 2%sodium bicarbonate solution is added. The solution is saturated byaddition of 23 g of sodium chloride and extracted with methylenechloride (1 X 200 ml and 3 X 100 ml). After drying over sodium sulfateremoval of the methylene chloride in vacuo gives 142 g of crude cis-3-hexene2,5-dione which by GLC analysis is about 90% product having thestructure:

EXAMPLE 11 (Preparation of 3Thioacetyl-2,S-hexanedione) In a 1000 mlround bottom flask fitted with magnetic stirrer, thermometer, additionfunnel and reflux condenser are placed 142 g of crude cis-3-hexane-2,5-dione (Example 1), 380 m1 of ether and 5 drops of piperidine. Thioacetic acid (96.6g) is added over a period of 1 hour. When about Vs ofthe thio acetic acid is added the solution begins to reflux whichcontinues during the remainder of the addition. After addition iscomplete the mixture is allowed to stand for minutes. Ether is thenremoved in vacuo (water asperator) to give 235 g of crude materialcontaining about 91% 3-thioacetyl-2,5-hexanedione. Distillation of a 134g portion of the crude gives 84.5 g of 3-thioacetyl-2,5- hexanedioneboiling at 86 to 87C at 0.5 torr. NMR, IR and mass spectral analysisconfirm the structure,

EXAMPLE Ill (Preparation of 2,5-Dimethyl-3-thioacetyl furan usingisopropenyl acetate) In a 500 ml three necked round bottom flask fittedwith reflux condenser, thermometer, mechanical stirrer and additionfunnel is placed 225 ml of isopropenyl acetate. The isopropenyl acetateis heated to reflux and 0.5 ml of concentrated sulfuric acid is added. Asolution of 25 g of 3-thioacetyl furan (produced according to Example11) in 25 ml of isopropenyl acetate is added over a 20 minute periodwhile maintaining reflux. The mixture is heated at reflux for anadditional 20 minutes and then cooled to room temperature during whichtime g of sodium bicarbonate is added. After removal of isopropenylacetate in vacuo (35 at 20 mm), 50 ml of benzene is then added and themixture is placed in a separatory funnel. 10 ml of water is then addedto the mixture, and when carbon dioxide evolution stops, the aqueouslayer is separated. Concentration in vacuo (35 bath, 20 mm) of theorganic phase gives 22.2 g of a dark brown oil. Distillation of the oilgives 16.5 g of 2,5-dimethyl-3-thioacetyl furan boiling at 47 to 48 C at0.25 mm.

EXAMPLE IV (Preparation of 2.5-Dimethyl-3-fu ranthiol) In a 1000 ml,three-necked flask fitted with thermometer, reflux condenser, nitrogeninlet and mechanical stirrer is placed 35 g of 2,5-dimethyl-3-thioacetylfuran (Produced by the process of Example 111) and 350 ml of sodiumhydroxide solution. The two phase mixture is heated to reflux and after35 minutes becomes homogeneous. The mixture is heated another minutesand cooled to room temperature. The pH of the solution is adjusted to 1by the addition of 310 ml of 20% sulfuric acid and the resulting mixtureextracted with ether (3 X 100 ml). Washing of the combined ethersolutions with saturated sodium chloride solution (4 X 75 ml), dryingwith anhydrous sodium sulfate and solvent removal in vacuo (C at 55 mm)gives 26.2 g of crude material. Distillation of the crude material gives17.3 g of 2,5-dimethyl-3-furanthio1 boiling at 79C at 43 mm. MS, NMR andIR analysis confirm the material as 2,5-dimethyl-3-furanthiol.

EXAMPLE V (Preparation of 3-Mercapto-2,5-hexanedione) To 150 ml of a 2%sodium hydroxide solution in a flask fitted for stirring is added 10 gof 3-thioacetyl-2,5- hexanedione. After stirring for 1 hour the pH ofthe mixture is adjusted to 5-6 by the addition of dilute (10%)hydrochloric acid, the solution is saturated with sodium chloridesolution and extracted with ether (4 X 25 ml). The ether extracts arecombined, washed with saturated sodium chloride solution (15 ml), driedand concentrated in vacuo to give 6.2 g of crude3-mercapto2,5-hexanedione. Vacuum distillation gives 2.5 g of3-mercapto-2,5-hexanedione boiling at 57-59C at 0.85 torr. NMR. IR andmass spectral analysis confirm the structure as 3-mercapto2,5hexanedione.

EXAMPLE VI (Preparation of 2-Methyl-3-furanthiol) A. 4-Oxo-2-pentanalInto a 5 liter, three-necked flask fitted with mechanical stirrer,thermometer and vacuum take-off are placed 600 g of2-methyl-2,5-dimethoxy-2,5- dihydrofuran and 2400 ml of deionized water.After 20 minutes of stirring at room temperature, the mixture becomeshomogeneous and has a pale yellow green color. Analysis of a sample ofthe reaction mixture by GLC after 3.25 hours shows 22% methanol, 67%4-oxo-2-pentanal and 9% starting material. Vacuum (26 torr.) is appliedto the reaction mixture while maintaining the temperature of thereaction mixture between 25 and 30C. After 3.25 hours GLC analysis shows13% methanol. 82% 4oxo-2-pentanal and 3.2% starting material. The vacuumis removed and the reaction mixture is allowed to stand at roomtemperature overnight. Analysis after standing overnight shows 12.9%methanol, 85% 4-oxo-2-pentanal and 2.1% starting material. B.3-Thioacetyl-4-oxo-pentanal In a 5 liter, three-necked flask fitted withmechanical stirrer, thermometer and addition funnel are placed 2325 m1of the solution obtained in (A) and 2 ml of piperidine diluted in 5 mlof water. To this solution is added a mixture ofthiolacetic acid (292.3g) and piperidine (13 ml) over a 20 minute period. After standing anadditional 10 minutes,20 ml of concentrated hydrochloric acid is added,the resulting mixture poured into a separatory funnel and the oil layerremoved. The aqueous layer is extracted with benzene (500 ml) andmethylene chloride (2 X 500 ml). The benzene extract is combined withthe oil layer and the mixture is dried over sodium sulfate. Themethylene chloride extracts are combined and dried over sodium sulfate.Solvent removal in vacuo (4045 bath at 15 torr.) gives 414.5 g of crudeoil from the benzene extract and 172.5 g of crude oil from the methylenechloride extracts. The crude 3-thioacetyl-4-oxo-pentanal is used as-isin the next step. C. 2-Methyl-3-thioacetyl furan In a 12 liter,three-necked flask fitted with stirrer, reflux condenser, thermometerand addition funnel are placed 2950 ml of isopropenyl acetate and 2 mlof concentrated sulfuric acid. The mixture is heated to reflux and asolution of crude 3'thioacetyl-4-oxo-pentanal (587 g) (obtained in Part(B) supra) in 1,170 ml of isopropenyl acetate is added over a 35 minuteperiod. After refluxing an additional 40 minutes sodium bicarbonate (35g) is added and removal of excess isopropenyl acetate in vacuo iscommenced. The pressure is gradually decreased from 200 to 30 torr. asthe temperature of the reaction mixture drops from C to 30C at whichtemperature it is maintained until the volume of the reaction mixture isabout 1500 ml. The material is further concentrated in vacuo (bathtemperature 50C and 5 torr.) to form a dark brown oil. The concentrateis diluted with 750 ml of benzene and washed with 250 ml of water. Afterdrying over sodium sulfate solvent removal in vacuo (4050C bathtemperature and 10 mm) gives 647 g ofa dark brown oil. Distillation ofthis oil gives 26.8 g of material boiling at 67-70C at 1.1 mm. which is62% 2methyl-3-thioacetylfuran. Redistillation gives g of2-methyl-3-thioacetylfuran of 86% purity determined by GLC boiling at73-76C at 5.8 to 6.2 mm Hg. pressure. D. Hydrolysis of2-Methy13-thioacetylfuran 2-methyl-3-furanthiol A 5% solution (1500 ml)of sodium hydroxide in water is heated to reflux under nitrogen. Whenreflux commences 151 g of 2-methyl-3-thioacetylfuran is added over aminute period. After 5 minutes heating is stopped and the mixtureallowed to cool. When the temperature reaches 30C, 258.1 g of sodiumdihydrogen phosphate monohydrate and 10 ml of acetic acid are added.After the salt is dissolved the mixture is extracted with methylenechloride (3 X 250 ml). After drying the methylene chloride extracts byfiltration through sodium sulfate and washing the sodium sulfate with100 ml of methylene chloride, the combined methylene chloride solutionsare concentrated in vacuo (30 at 25 mm) to yield 94.8 g of crude2-methyl-3- furanthiol. Distillation gives 64.6 g of 2-methyl-3-furanthiol boiling at 5556 at 4142 mm.

EXAMPLE VII (Preparation of 2-Thioacety1furan) A. Preparation of2-Butene-l,4-dial A mixture of 2,5-dimethoxy-2,5-dihydrofuran g), water(80 ml) and acetic acid (3 drops) is stirred for 105 minutes at roomtemperature, 22 minutes at 40C and 90 minutes between 60C and 75C. GLCanalysis at this point indicates 15.7% starting material and 83.5%2-butene-l,4-dial. The mixture is cooled to 25C and sodium bicarbonate(0.3 g) is added. B. Preparation of 3-Thioacetyl-1,4-butanedial To theaqueous solution obtained in paragraph A, supra, is added 10 g ofthiolacetic acid during a 14 minute period. During the addition, thetemperature iskept below C by intermittent application of a coolingbath. After 110 minutes, the reaction mixture is extracted withmethylene chloride (3 X ml). The combined methylene chloride extractsare dried and then concentrated in vacuo to give 17.3 g of yellow oilcontaining about 80% 2-thioacetyl-l,4-butanedial. The compound isidentified through mass spectral, NMR and IR analysis as having thestructure:

M.S. No molecular ion; remaining peaks in decreasing intensity 43, 29,27,45, 55,60, 84, 100 and 142 m/e units.

NMR (CDCl;,) 6 2.38 (s,3) 3.02 (Multiplet 2 .l=l0H 4.46 (1,1, J=l0 H9.40 (s,1) and 9.68 (3,1 ppm.

1R (thin film) 2850, 2750, 1720, 1700 (shoulder),

1388, 1352, 1132 and 958 cm C. Preparation of 3-thioacetylfuran 1n a 500ml flask fitted with mechanical stirrer, reflux condenser. additionfunnel and thermometer are placed 109 ml of isopropenyl acetate and 0.2ml of concentrated hydrochloric acid. The resulting mixture is heated toreflux and, when reflux commences, a solution of crude2-thioacetyl-1,4-butanedial (produced in paragraph B, supra) in 70 ml ofisopropenyl acetate is added over a 31 minute period while maintainingreflux. The mixture is heated at reflux for 15 minutes after addition iscomplete. After cooling to 25C, so dium bicarbonate (2.4 g) is added andthe mixture stirred for 20 minutes. The mixture is concentrated in vacuoand 670 ml of benzene and 25 ml of water are added. The benzene layer isseparated, washed with saturated sodium bicarbonate solution (5 X 25ml), dried with sodium sulfate and concentrated in vacuo to give 14.7 gof an oil. Vacuum distillation gives 1.24 g of 97.5% pure3-thioacetylfuran. Mass spectral, NMR and IR analysis confirm thestructure as 3- thioacetylfuran.

Mass spectrum, molecular ion, then peaks in decreasing intensity; 142,43, I00, 45, 69, 71, 72 and 73 m/e units.

NMR (CDCl;,) 8 2.34 (5,3), 6.38 (d,1, 1=1H and 7.46 (I71,2,.1=lHz) ppm.IR (thin film) 3120, 1710, 1495,1355, 1197, l147),1l10, 1072,1010, 953.940, 870 and 795 cm.

EXAMPLE V111 (Preparation of 2-Methyl-3-thioisobutyrylfuran) A mixtureof 1.0 g of 2-methyl-3-furanthiol, 0.70 g of pyridine and 10 ml ofdiethyl ether is placed in a flask and 0.93 g of isobutyryl chloride isadded. After stand- 1 ing 30 minutes the resulting mixture is filteredand the filtrate concentrated in vacuo to a greenish yellow oil weighing1.0 g. The product is isolated by preparative GLC. NMR, IR and massspectral analysis confirmed the structure of the product as2-methyl-3-thio isobutyrylfuran.

Similarly prepared using 2-methyl3-furanthiol are:

2Methyl-3-thioacyl furan or 2-Methyl-3-thioaroyl furan Reaction ProductAcylating or aroylating Agent lsovaleryl chloride Furoyl chlorideOctanoyl chloride Pivaloyl chloride 2-Mcthyl-3-thioiso\'aleryl furan2-Methyl-3-( Z-Ihiofuroyl) furan Z-Methyl-3-thio-octanoyl furan2-Methyl-3-thio-pivaloyl furan EXAMPLE [X The following formulation isprepared:

The 2,5-dimethyl-3-thiobenzoyl furan has a sweet blending effect,imparting a meat taste of a nondescript character leaning towardschicken meat. This chemical helps reduce the typical hydrolyzedvegetable protein taste and ties in and rounds up the other meat likechemicals in the formula.

EXAMPLE X The following formulation is prepared:

-Continued liigredieiit Parts by Weight Ingredient Parts by WeightLiquid hydrolyzed vegetable protein )1) gi g ffi i 4-Methyl-heiahydioxy-eihylthiayole 5 5 7'00 g g s gifil zl (1)012.5-l)imethyl-3-thioisoviileryl furan (L004 m tational up m 0150 m 'iDifurfuryl disullide .49 s'gm git kcumL 82,88 Delta decalactone 20510002.S-D lm$1l1)l 3-KhlOhXAlHUyl furan lit )0 10 Delta Lkdcculdcmne 408396The 2,S-dimethyl-3-thiohexan0yl furan adds Specific The F abm'e butterflavor composition at 0.004% adds a sweet meat notes to the formulation.It is sweet and creamy I creaminess to the butter fulness. Flavoringmargarine and very specifically reminiscent of white meat I at 0.04% andapproximately the same for baked prodchicken. in general, it upgradesthe formula by impartg ,1 dminct meat Character ucts puts thisapplication at l to 3 parts per billion.

EXAMPLE XI EXAMPLE XlV In Royal instant vanilla pudding (ingredients:sugar I'h f J z e Olkmmg formuldtmn ls preplred and dextrose, precookedstarch, sodium and calcium phosphates, salt, vegetable shortening,artificial flavor lug-fluent by weigh, and color, vegetablemonoglycerides, butylated hylh l i droxy anisole, butylated hydroxytoluene. citric acid Liquit yr ro \ZLL vegetable protein 90 i 4MwhyLhclwhydmxycthy] minim 5 g and corn oil, produced by StandardBrands, lnc. New Tetrahydro ll'iiophene-fl-one 1 York, NY.) at 80 partsper billion (0.008 grams of hlrlm)" P (ml 01% dilution of2,5-dimethyl-3-thioisovalervl furan in Z-Noncnal 050 Dummy] dimmdc 49100 grams of pudding) a panel evaluation (5 panelists) Dimeihy'l sulfide50 was performed. The panel of five agreed that thepudglgf{I,,I,fif,fffifl, rum], 3U ding was much sweeter with no offcharacter than such pudding without the said2,5-dimethyl-3thioisoraleryl furan. The panel of five also agreed thatthe general The 2,5-dimethyl-3-thioacetyl furan causes the aboveOver-1111 11mm? of the Said puddingwus eilhlmcid 11$ formulation to bedistinctly roast meat in character and Compared with the same puddingwithout the in aroma and taste. It is typically gravy-like (roast meat y-3 0 s y furangravy). The ,5 dimethyl 3 tliioacetyl furan also irnEXAMPLE XV parts a slight nutty note which can be associated with theroast meat gravy A panel evaluation similar to that carried out inExample XlV was carried out on Royal instant chocolate EXAMPLE 40pudding containing 2.5dimethyl-thioisovaleryl furan at The f u i f l tii prepared; a level of 80 parts per billion. The five panelists agreedthat the 2,5-dimethyl-thioisovaleryl furan has a definite blending androunding off effect on the pudding flavor. lngrsdicm Parts y Wvigh! inaddition, two of the anelists thou ht that the p g Liquid hydrolyzedvegetable protein 90 2,S-dimethyl-3thioisovaleryl furan deepened thechar- 4-Methy|-hcta-hydroxy-ethyl-thiazole 5 acter of the cocoa itselfand all five panelists agreed gmf t'fgfe$233315 that the2,5-dimethyl-3thioisovaleryl furan improved LNOMM, the general flavorcharacter of the chocolate pudding Difurfuryl dis nlfide .49 as comparedto the same chocolate pudding without ai i ig g g 8:28 50 said2,5-dimethyl-3thioisovaleryl furan. 2Methyl3thioacety| furan 2.00 Whatis claimed is:

' l. A process for altering the organoleptic properties t of a foodstuffwhich comprises adding to said foodstuff The z'methyl'3thloacetyl furanCauses the above asmall but effective amount, to impart to saidfoodstuff formulation to be distinctly roast meat in character and ameaty aroma d taste, of a 3-f lthi t in aroma and taste causes it to betyp cally gravy-like pound l d f h group consisting f; (roast meatgravy). The 2methyl-3-thioacetyl furan s 3-Thi l f stronger andconsequently the flavor is more predomi- 2 M h 1 3 hi f nantly roastmeat. The sweet and roast nut notes are 2,5-Di 1h 1 3 thi er l furan;very reminiscent of roast meat gravy. 2-Methyl 3-thi is butyryl furan;

EXAMPLE XIII 2,5-Dimethyl-3-thioisobutyryl furan;

Z-Meth l-3-thioisovaler furan; Y Y The following formulation is prepared(butter flavor 2 M th l-3-(2 thi f l) f ran; formulation):2,5-Dimethyl-3(2-thiofuroyl) furan;

2-Methyl-B-thiooctanoyl furan;

Ingredient Parts by Weight Diacetyl 60.000

2,5-Dimethyl-3-thiooctanoyl furan; 2,5-Dimethyl-3-thiobenzoyl furan;2,5-Dimethyl-3-thiopropionyl furan;

2-Methyl-3-thiopivaloyl furan;

2.5-Dimethyl-3-thiopivaloyl furan;

2,5-Dimethyl-3-thiohexanoyl furan; 2-Propyl-3-thioacetyl furan;

2, -Dimethyl-3-thio-(Z-MethyI-Z-pentenoyl) furan;

2,5-Dimethyl-3-thiocinnamoyl furan; and

2,5-Dimethyl-3-thio(m-toluyl) furan.

2. The process for altering the flavor of a foodstuff of claim 1 whereinthe 3-furylthioester compound is 3- thioacetyl furan.

3. The process for altering the flavor of a foodstuff of claim 1 whereinthe 3-furylthioester compound is Z-methyl-B-thioacetyl.

4. The process for altering the flavor of a foodstuff of claim 1 whereinthe 3-furylthioester compound is 2.5-dimethyl-3-thioacetyl furan.

5. The process for altering the flavor of a foodstuff of claim 1 whereinthe 3-furylthioester compound is 2-methyl-3-thioisobutyryl furan.

6. The process for altering the flavor of a foodstuff of claim 1 whereinthe 3-furylthioester compound is 2,5-Dimethyl-3-thioisobutyryl furan.

7. The process for altering the flavor of a foodstuff of claim 1 whereinthe 3-furylthioester compound is 2-Methyl-3-thioisovaleryl furan.

8. The process for altering the flavor of a foodstuff of claim 1 whereinthe 3-furylthioester compound is 2-methyl-3(2-thiofuroyl) furan.

9. The process for altering the flavor of a foodstuff of claim 1 whereinthe 3'furylthioester compound is 2,5-Dimethyl-3(thiofuroyl) furan.

10. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2-methyl-3-thiooctanoyl furan.

11. The process for altering the flavor of a foodstuff of claim Iwherein the 3-furylthioester compound is 2,5-dimethyl-3-thiooctanoylfuran.

12. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2,5-dimethyl-3-thiobenzoylfuran.

13. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2,5dimethyl-3-thiopropionylfuran.

14. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2-methyl-3-thiopivaloyl furan.

15. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2,5-dimethyl-3-thi0pivaloylfuran.

16. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2,5-dimethyl3-thiohexanoylfuran.

17. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2-propyl-3-thioacetyl furan.

18. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2,-5-dimethyl-3-thio-(Z-Methyl-Z-pentenoyl) furan.

19. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2,5-dimethyl-3-thiocinnamoylfuran.

20. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2,5-dimethyl-3-thio(m-toluyl)furan.

1. A PROCESS FOR ALTERING THE ORGANOLEPTIC PROPERTIES OF A FOODSTUFFWHICH COMPRISES ADDING TO SAID FOODSTUFF A SMALL BUT EFFECTIVE AMOUNT,TO IMPART TO SAID FOODSTUFF A MEATY AROMA AND TASTE, OF A3-FURYLTHIOESTER COMPOUND SELECTED FROM THE GROUP CONSISTING OF:3-THIOACETYL FURAN; 2-METHYL-3-THIOACETYL FURAN;2,5-DIMETHYL-3-THIOACETYL FURAN; 2-METHYL-3-THIOSOBUTYRYL FURAN;2,5-DIMETHYL-3-THIOSOBUTYRYL FURAN; 2-METHYL-3-THIOSOVALERYL FURAN;2-METHYL-3-(2-THIOFUROYL) FURAN; 2,5-DIMETHYL-3-(2-THIOFUROYL) FURAN;2-METHYL-3-THIOOCTANOYL FURAN; 2,5-DIMETHYL-3-THIOOCTANOYL FURAN;2,5-DIMETHYL-3-THIOBENZOYL FURAN; 2,5-DIMETHYL-3-THIOPROPIONYL FURAN;2-METHYL-3-THIOPIVALOYL FURAN; 2,5-DIMETHYL-3-THIOPIVALOYL FURAN;2,5-DIMETHYL-3-THIOHEXANOYL FURAN; 2-PROPYL-3-THIOACETYL FURAN;2,5-DIMETHYL-3-THIO-(2-METHYL-2-PENTENOYL) FURAN;2,5-DIMETHYL-3-THIOACCANAMOYL FURAN; AND 2,5-DIMETHYL-3-THIO(M-TOLUYL)FURAN.
 2. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 3-thioacetyl furan.
 3. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2-methyl-3-thioacetyl.
 4. The process foraltering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2,5-dimethyl-3-thioacetyl furan.
 5. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2-methyl-3-thioisobutyryl furan.
 6. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2,5-Dimethyl-3-thioisobutyryl furan.
 7. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2-Methyl-3-thioisovaleryl furan.
 8. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2-methyl-3(2-thiofuroyl) furan.
 9. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2,5-Dimethyl-3(thiofuroyl) furan.
 10. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2-methyl-3-thiooctanoyl furan.
 11. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2,5-dimethyl-3-thiooctanoyl furan.
 12. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2,5-dimethyl-3-thiobenzoyl furan.
 13. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester cOmpound is 2,5-dimethyl-3-thiopropionyl furan.
 14. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2-methyl-3-thiopivaloyl furan.
 15. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2,5-dimethyl-3-thiopivaloyl furan.
 16. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2,5-dimethyl-3-thiohexanoyl furan.
 17. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2-propyl-3-thioacetyl furan.
 18. Theprocess for altering the flavor of a foodstuff of claim 1 wherein the3-furylthioester compound is 2,5-dimethyl-3-thio-(2-Methyl-2-pentenoyl)furan.
 19. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2,5-dimethyl-3-thiocinnamoylfuran.
 20. The process for altering the flavor of a foodstuff of claim 1wherein the 3-furylthioester compound is 2,5-dimethyl-3-thio(m-toluyl)furan.